Environment and Breast Cancer: Science Review

Cancer incidence and mortality in women occupationally exposed to chlorophenoxy herbicides, chlorophenols, and dioxins
Kogevinas, M., Saracci, R., Winkelmann, R., Johnson, E. S., Bertazzi, P. A., Bueno de Mesquita, B. H., Kauppinen, T., Littorin, M., Lynge, E., Neuberger, M., et al., Cancer Causes and Control. 1993. 4:6, 547-53.

Topic area
Environmental pollutant - Pesticide, chlorophenoxy herbicide, chlorophenols,
Environmental pollutant - Pesticide, chlorophenoxy herbicide, chlorophenols,
Study design
Other: Cohort mortality and incidence follow up.
Other: Cohort mortality and incidence follow up.
Funding agency
Other: National Cancer Institute of Canada
Other: National Cancer Institute of Canada

Study Participants
Menopausal Status
Post menopausal
The menopausal status of women included in this study is listed here.
Pre menopausalPost menopausal
Number in Cohort
Cohort: 701
Cohort: 701
Country where study was conducted
International
International
Participant selection: Inclusion and exclusion criteria
Criteria used to select participants in the study.
International Register of Workers occupationally exposed to chlorophenoxy herbicides, chlorophenols, and dioxins. Reference: national death and incidence rates

Exposure Investigated
Exposures investigated
Worked more than one month in production or spraying of chlorophenoxy herbicides and chlorophenols, which are expected to be contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in jobs assessed to be exposed.
Worked more than one month in production or spraying of chlorophenoxy herbicides and chlorophenols, which are expected to be contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in jobs assessed to be exposed.
How exposure was measured
Job history
Job history
Exposure assessment comment
Exposed workers are likely to be exposed to many other chemicals as well.
Exposed workers are likely to be exposed to many other chemicals as well.

Statistical Analysis
Ethnic groups with separate analysis
If this study provided a separate analysis by ethnic or racial group, the groups are listed here.
No
Confounders considered
Other breast cancer risk factors, such as family history, age at first birth, and hormone replacement therapy use, that were taken into account in the study.
Not adequately addressed.
Genetic characterization included
If the study analyzed relationships between environmental factors and inherited genetic variations, this field will be marked “Yes.” “No”, if not.
No
Description of major analysis
Standardized mortality and incidence ratios based on the Poisson distribution.
Standardized mortality and incidence ratios based on the Poisson distribution.
Strength of associations reported
SIR = 91 (95% CI 36-187), 7 cases
SMR = 30 , 1 case
Probable TCDD exposure SIR 86 (2-480), 1 case
SIR = 91 (95% CI 36-187), 7 cases
SMR = 30 , 1 case
Probable TCDD exposure SIR 86 (2-480), 1 case
Results Comments
Inadequate statistical power. Healthy worker effects not addressed. Includes 169 exposed workers probably exposed to TCDD and 532 exposed women unlikely exposed to TCDD.
Inadequate statistical power. Healthy worker effects not addressed. Includes 169 exposed workers probably exposed to TCDD and 532 exposed women unlikely exposed to TCDD.

Author address
Unit of Analytical Epidemiology, International Agency for Research on Cancer, Lyon, France.
Unit of Analytical Epidemiology, International Agency for Research on Cancer, Lyon, France.